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CC-SA.
(8) http://en.wikipedia.org/wiki/Image:
Fileisnotcorruptedactuallyupload3453405.jpgNormal Vision,Myopia.
(9) Tomasz Trojanowski. Royalty Free.
(10) Centers for Disease Control and Prevention.
http://en.wikipedia.org/wiki/Image:Neisseria_meningitidis.jpg. Public
Domain.
(11) http://commons.wikimedia.org/wiki/File:Synapse.png. Public Domain.
(12) http://commons.wikimedia.org/wiki/File:First_red_cherries_001.jpg.
CC-BY.
(13) http://commons.wikimedia.org/wiki/File:2006-01-14_Surface_waves.jpg.
GNU-FDL.
(14) http://www.jyi.org/articleimages/539/originals/img0.jpg. GNU-FDL.
(15) http://commons.wikimedia.org/wiki/File:DSCN9696_windsorbball_e_300.jpg.
GNU-FDL.
(16) http://commons.wikimedia.org/wiki/Image:EM_spectrum.svg. CC-BY-SA.
(17) http://en.wikipedia.org/wiki/File:Focus_in_an_eye.svg. CC-BY-SA.
(18) http://commons.wikimedia.org/wiki/Image:Kaktus.jpg. CC-BY.
(19) http://commons.wikimedia.org/wiki/File:Neuron.jpg. Public Domain.
(20) http://en.wikipedia.org/wiki/File:
Human_eye_cross-sectional_view_grayscale.png. Public Domain.
(21) [Dreamstime.com ]. Royalty Free.
(22) CK-12 Foundation.
http://commons.wikimedia.org/wiki/File:Kidney_beans.jpg
http://commons.wikimedia.org/wiki/Image:Various_grains.jpg. (d)Public
Domain, GNU-FDL.
(23) http://www.lmpc.edu.au/resources/Science/research_projects/diag&
draw/nervereflexarc.gif.
(24) Volker Wille. Royalty Free.